Smoky Sea Stock

The waters of Tosa Bay, off the Kōchi coast, teem with a tuna-like fish called katsuo, or bonito. In the early summer months the catch is served fresh, but year-round bonito is dry-roasted to make fish flakes called katsuo bushi. These fish flakes are used to make basic sea stock and to add a smoky flavor to a number of other sauces and stocks as well. This stock, named after the bay where bonito is caught, can be used in lieu of the basic sea stock in any recipe.